The death of the father
Many of the plot details of this novel take the reader through archetypal sequences, beginning with a child who is largely the product of his wilderness upbringing (he spend a lot of time in the woods and is therefore similar symbolically to "L'enfant Sauvage"). His inciting incident is the death of his father. The father dies while he is away, and so the symbolic question is raised: How will Fleetwood fare in his newly attained dominion of home and self? He now has no patriarch, but has become his own patriarch. His goal (archetypally speaking) is to adopt his father's essence and accept responsibility, but the novel is a drama about how he struggles to do just that.
The journey through nations
The inciting incident is paired symbolically with a coming-of-age tour of Europe that many of the people in his community did when they were old enough to travel. The purpose of this trip in general is to give a broader sense of the world to young men, but also to connect them with the various business partnerships of their fathers to continue good trade relationships through generations. Fleetwood's journey is much different though, because to him it is like a spiritual journey into the unknown and back home again, except when he comes home, his father has died. It is a bit like "trial by fire."
The orphan wife
We know from implication what happens to Fleetwood for the two and a half decades that the novel skips. He had a hard time of it. He is finally married at the age of 45, and he doesn't really enjoy intimacy with anyone. He picks this symbolic spouse for himself: a highly dependent, socially damaged orphan who quickly attaches herself to him. Their relationship is dysfunctional because she longs for his approval, but he doesn't have approval within himself to offer her. When Gifford starts whispering in Fleetwood's ear, the marriage quickly falls apart. Their co-dependent relationship is easily exposed through paranoia and conspiracy.
The anti-brother
Gifford is a cousin of Fleetwood who is like Cain to Abel. He is not the loving family man that Fleetwood believes him to be. In reality, his goal is to exploit the emotional weaknesses of Fleetwood and his wife, ingratiating himself in their lives through fostering dependency, and then stealing or inheriting the estate. This archetypal character has echoes in all of world literature: Romulus and Remus, Cain and Abel, Jacob and Esau, etc.
Anagnorisis
Anagnorisis is a climactic motif from tragedy first categorized by Aristotle. The idea is that a character with a flaw is driven to a point of climactic revelation where they are undone by that flaw so thoroughly and publicly that they can no longer ignore their mistakes. This happens to Fleetwood when he abandons his responsibilities and his wife, and is attacked by thieves (a symbol for the chaos within people to harm each other) and then saved by a father-figure (Louisa's father), who explains that if Fleetwood had had the emotional endurance to be patient, he would have learned that the love letter that ended his marriage was not even about his wife, but Louisa. He jumped to conclusions with emotional intensity—so in the aftermath he fixes his mistake and leaves. He still doesn't want to be married.
